For persons with the need of being near to a toilet, they being toddlers that are about learning to use a toilet or adults with incontinence problems, it may be a substantial restriction in their freedom of movement to be near a permanently installed water closet or alternatively to carry a chemical closet or a chamber-pot.
It is particularly troublesome to go on trips away from urban areas and into the nature where the necessary facilities are far away, and the possibility of bringing along appliances is limited to what may be carried in a small bag or a pocket.
Through the years, various solutions of inflatable receptacles have been invented which may serve as chemical closet or chamber-pot.
An example is shown in the document WO 91/03199 concerning an inflatable potty for children. In principle, this consists of two toroidal inflated superposed units, and where the outer diameter of the upper ring is less than the outer diameter of the lower ring when both rings are inflated. Even if this design is created with the intention of good stability of the chamber-pot, there is a limit to how high such a chamber-pot can be if sufficient stability is to be maintained. This entails a design where the chamber-pot is rather low, and where the lower ring will interfere with the person's foot resting on the base, making a chamber-pot of this design unsuitable for most people.
GB 2 220 566 A shows an inflatable chamber-pot designed as three torus rings of equal size. This chamber-pot will be experienced as very unstable by the user, as even small lateral movements will cause elastic deformation of the pot. In the case of an restless child pushing the upper end of the pot sideways, this lateral action of force on a chamber-pot according to this design will cause a significant deformation at one side of the support face of the chamber-pot, causing the pot to tilt and maybe overturn.